Re: per-paragraph auto-direction, a.k.a. dir=uba

>>    * Using dir=auto with autodirmethod=uba would (by default) set
>>      unicode-bidi to "uba" and direction according to first-strong.
>>      (Note that this includes leaving direction at the inherited value
>>      if the content is neutral.)
>>    * For elements other than <textarea>, unicode-bidi:uba is treated as
>>      unicode-bidi:isolate.
>>    * On <textarea>, unicode-bidi:uba means that:
>>          o The UBA on the textarea content is invoked specifying only a
>>            default paragraph level (in icu4j terminology, either
>>            LEVEL_DEFAULT_LTR or LEVEL_DEFAULT_RTL), based on the the
>>            element's own direction value as calculated above. (This
>>            makes the all-neutral paragraphs use the same direction as
>>            the first paragraph that is not all-neutral.)
>>          o Each UBA paragraph’s lines’ alignment is determined by the
>>            paragraph’s resolved base level when the element's
>>            text-align is start or end.

> This is too complicated.

I assume that the parts that to which you object are the ones you then
mentioned (which I list below), while everything else (e.g. adding the uba -
or plaintext - value to the unicode-bidi CSS property) is ok.

> I suggest "plaintext" instead of "uba" because it's clearer what the
> behavior and the intended use case is. (Since we're only allowing uba
> on <textarea> and using dir=auto for first-strong, we don't need the
> name to be so cryptically short.)

Sounds good to me.

> If uba cannot in fact be triggered on anything
> other than a <textarea>, then it should not be allowed on anything other
> than a <textarea>. I suggest having
> dir=ltr|rtl|auto|plaintext
> autodirmethod=first-strong|any-rtl

I presume you mean that dir=plaintext is ignored on elements other than
<textarea>. Also, unicode-bidi:plaintext is ignored (i.e. treated as
unicode-bidi:normal) on elements other than <textarea>.

In my opinion, having both dir=auto and dir=plaintext, especially when there
is also autodirmethod, seems clunky to me. What's wrong with having just
dir=auto, with plaintext being one of the autodirmethod values? If you want
to disallow plaintext on anything other <textarea>, we can specify that
unicode-bidi:plaintext is ignored (i.e. treated as normal) on elements other
than <textarea>.

Aharon

On Tue, Sep 14, 2010 at 8:56 PM, fantasai <fantasai.lists@inkedblade.net>wrote:

> On 09/14/2010 08:39 AM, Aharon (Vladimir) Lanin wrote:
>
>> I second Mati's proposal. As Ehsan has pointed out <textarea readonly>
>> can be used to display plain text (as opposed to edit it), even though
>> somewhat awkwardly. And if we work out a bigger proposal, we can tweak
>> the bugs filed on HTML5 and CSS3. Right now it is imperative to produce
>> a new draft of the proposal and file the bugs (October 1 deadline for
>> HTML5..., apparently).
>>
>> I do want to put dir=uba under the dir=auto umbrella, via
>> autodirmethod=first-strong|any-rtl|uba. autodirmethod inherits; dir does
>> not. The default would probably be first-strong.
>>
>> Is this agreeable to everyone? Please respond.
>>
>> Here is a quick spec for dir=auto:
>>
>>    * Using dir=auto with autodirmethod=uba would (by default) set
>>
>>      unicode-bidi to "uba" and direction according to first-strong.
>>      (Note that this includes leaving direction at the inherited value
>>      if the content is neutral.)
>>    * For elements other than <textarea>, unicode-bidi:uba is treated as
>>      unicode-bidi:isolate.
>>    * On <textarea>, unicode-bidi:uba means that:
>>          o The UBA on the textarea content is invoked specifying only a
>>
>>            default paragraph level (in icu4j terminology, either
>>            LEVEL_DEFAULT_LTR or LEVEL_DEFAULT_RTL), based on the the
>>            element's own direction value as calculated above. (This
>>            makes the all-neutral paragraphs use the same direction as
>>            the first paragraph that is not all-neutral.)
>>          o Each UBA paragraph’s lines’ alignment is determined by the
>>
>>            paragraph’s resolved base level when the element's
>>            text-align is start or end.
>>
>
> This is too complicated. If uba cannot in fact be triggered on anything
> other than a <textarea>, then it should not be allowed on anything other
> than a <textarea>. I suggest having
>
>  dir=ltr|rtl|auto|plaintext
>
>  autodirmethod=first-strong|any-rtl
>
> I suggest "plaintext" instead of "uba" because it's clearer what the
> behavior and the intended use case is. (Since we're only allowing uba
> on <textarea> and using dir=auto for first-strong, we don't need the
> name to be so cryptically short.)
>
>  # The part of the text after the first X characters (where the text in
>>
>> nodes excluded above are not part of the count). Do we need this? If
>> so, what's a good X value? 100?
>>
>
> And I think that for any-rtl having an X value is both better for
> performance and more likely to give good results. If the first X
> characters are LTR, where X is longer than most LTR phrases commonly
> imported into RTL text, chances are any RTL characters after that
> are not indicating the paragraph's main direction.
>
> ~fantasai
>